The Hyperloop sounded like science fiction when the fantastic concept was first raised by engineer and entrepreneur Elon Musk.
Traveling through pneumatic tubes, Musk said the system said would enable travel from Los Angeles to San Francisco in less than 30 minutes, crossing a distance of 343 miles (552 kilometres) at more than 685 miles per hour (1,102 kilometres per hour.)
While the project may seem fantastical, additional details have been released on to the plan.
In his blog, Musk says if a massive investment is made in a new transportation system, the return should by rights be equally massive.
Musk’s thoughts veer from the obvious to the slightly bizarre. He says the system must be safer, faster, less expensive, more convenient, sustainable and self-powering, and “not disruptive to those along the route.”
In addition, it must also be able to operate in all kinds of weather and resistant to earthquakes.
The Hyperloop concept, in Musk’s opinion, is the right solution for high-traffic city pairings that are less than about 1,500 kilometres apart. Beyond that, he suspects that supersonic air travel will end up being faster and cheaper.
In a 50-page document, Musk expands on the $6 billion Hyperloop concept, which essentially consists of pods racing through vacuum tubes. He proposes the installation of an electric compressor system on the nose of the pod that essentially ingests incoming air to create a cushion or “air bearings.”
That would be akin to having a pump in the head of a syringe which actively relieve pressure. Air bearings, which use the same basic principle as an air hockey table, have been demonstrated to work at speeds of Mach 1.1 with very low friction. Aerodynamic simulations have shown that could potentially create a system that travels comfortably at 700 miles per hour.
Musk says this then necessitates questions as to whether a battery can store enough energy to power a fan for the length of the journey with room to spare.
“Based on our calculations, this is no problem, so long as the energy used to accelerate the pod is not drawn from the battery pack," Musk says.
"This is where the external linear electric motor comes in, which is simply a round induction motor (like the one in the Tesla Model S) rolled flat. This would accelerate the pod to a high subsonic velocity and provide a periodic reboost roughly every 70 miles. The linear electric motor is needed for as little as ~1% of the tube length, so is not too costly.”
The system can be self-powering through the installation of solar panels on top of the tube, which will generate far more energy than the Hyperloop needs to operate. This takes into account storing enough energy in battery packs to operate at night and for periods of extended cloudy weather. The energy can also be stored in the form of compressed air which then runs an electric fan in reverse to generate energy.
The key advantages of a tube as opposed to a railway track, argues Musk, are that it can be built above the ground on pylons as well as in prefabricated sections that are dropped into place and joined together with an orbital seam welder. Additionally, by building a system on pylons, where the tube is not rigidly fixed at any point, earthquake risk can be mitigated and the need for expansion joints will be reduced.
During peak periods, 40 capsules could move 840 passengers per hour. Each capsule could hold 28 people, and depart every 30 seconds with approximately 23 miles between capsules. Economically speaking, Musk estimates that passengers could expect to pay just $20 for a one-way journey.
Musk has again reiterated, however, that he does not have the time to dedicate to the concept personally but that a partnership arrangement or technology patenting agreement therefore are both a possibility.
A little more light has been shed but it appears the futuristic concept is still a long way from becoming a reality.